For a system that locks/unlocks doors of a vehicle using an electronic key, a keyless entry system and a passive entry system are well known. In the keyless entry system, when an electronic key is operated, the electronic key transmits a remote control signal to the vehicle side, and locking/unlocking of doors is performed based on the remote control signal. In the passive entry system, when a user's approach or touch on a door knob is detected, the vehicle side transmits a response request signal, and locking/unlocking of doors is performed based on a response signal which is sent back from an electronic key having received the response request signal.
Meanwhile, various types of in-vehicle apparatuses are mounted on a vehicle. A user can set, for example, a seat position, a door mirror angle, etc., according to his/her preferences. In addition, the user can also freely perform various types of settings of a car navigation apparatus, an audio apparatus, an air conditioning apparatus, etc. However, it is very cumbersome for the user to perform these settings every time he/she gets in the vehicle. For measures to deal with this, there is a method in which setting information of each in-vehicle apparatus is registered as customization information for each electronic key owner, and when a user gets in a vehicle, customization information is read based on his/her electronic key ID, and the setting of each in-vehicle apparatus is automatically performed. However, since the number of electronic keys to be provided to one vehicle is limited, this method has difficulty in dealing with, for example, carsharing where many and unspecified users share a vehicle.